Information-processing devices that are able to communicate with other users using a communication function are known.
The present disclosure provides technology for activating communication in a playgroup of a posted information sharing service.
There is provided a posted information sharing system including: a game processing unit that executes a multiplayer game application through a plurality of users each using a terminal; a group formation unit that forms a playgroup for playing the game application; and a posted information sharing unit that receives and stores posted information from the terminals, and/or outputs posted information to the terminals, wherein the posted information sharing unit manages the posted information in a plurality of groups, and the posted information sharing unit includes: a posted information storage unit that manages and stores, in the groups, posted information that is generated based on input of the terminals; a posted information display unit that, according to a request from the terminals, displays the posted information on the terminals in the groups; and an identification information management unit that manages identification information of the groups, the game processing unit includes: a group formation request unit that outputs, to the group formation unit, a playgroup formation request that specifies a group, according to input of the terminals, wherein the group formation unit is configured to form the users of terminals that specify the same group into a playgroup, based on the specified group.